[tinman386]

Ive got my oil filter adapter plate off my 350 when it was built. I notice that there is a washer in it with a spring and then a plastic piece. If i take this out it leaves an open hole. You can see the plastic piece when oil filter is off. First what is this for? And can it hurt anything if i leave it out? I'm thinking its some kind of bypass but im not sure how it works. The problem is if its needed i have to find a new spring as the original is so rotted it crumbled in my hand while cleaning it up. Which means i have to find the correct rate spring i would think.

[Jmark]

It is a bypass valve. It needs to be there! If yours is bad, just stop by any machine shop and ask if they have a spare or go to any GM dealer and buy a new one. They are all the same, no need to figure spring rate.

[engineczar]

Here ya go

http://www.competitionproducts.com/p...number=3952301

[MIKE FROM SM]

Or you can put a pipe plug in it with a little epoxy. This way all the oil goes through the filter. However, you will have to run a good filter and change more often. Most race type engines are like this.

[tinman386]

Thanks guys i appreciate your input. Ive seen the ones that eliminate the bypass at jegs. Im just not sure, would my oil pressure change or the flow rate change? Why is there a bypass to begin with? I think im going with the one that Engineczar put the link up for thank you very much for the link BTW I have been searching for several days for one of these and kept coming up empty. HOTRODDERS RULE

[jimfulco]

The bypass valve is there to protect the filter from excess pressure. On a cold start, the oil is thicker, and oil pressure can go way higher than normal. Some filters can't take the excess, and will blow out. The bypass valve prevents this.